.\" Copyright (c) 2006,2008 Joseph Koshy.  All rights reserved.
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.\" $Id: gelf_getshdr.3 3639 2018-10-14 14:07:02Z jkoshy $
.\"
.Dd August 27, 2006
.Dt GELF_GETSHDR 3
.Os
.Sh NAME
.Nm elf32_getshdr ,
.Nm elf64_getshdr ,
.Nm gelf_getshdr
.Nd retrieve the class-dependent section header
.Sh LIBRARY
.Lb libelf
.Sh SYNOPSIS
.In libelf.h
.Ft "Elf32_Shdr *"
.Fn elf32_getshdr "Elf_Scn *scn"
.Ft "Elf64_Shdr *"
.Fn elf64_getshdr "Elf_Scn *scn"
.In gelf.h
.Ft "GElf_Shdr *"
.Fn gelf_getshdr "Elf_Scn *scn" "GElf_Shdr *shdr"
.Sh DESCRIPTION
These functions return a pointer to the ELF Section Header data
structure associated with section descriptor
.Ar scn .
.Pp
Function
.Fn elf32_getshdr
retrieves a pointer to an
.Vt Elf32_Shdr
structure.
Section descriptor
.Ar scn
must be associated with an ELF descriptor of class
.Dv ELFCLASS32 .
.Pp
Function
.Fn elf64_getshdr
retrieves a pointer to an
.Vt Elf64_Shdr
structure.
Section descriptor
.Ar scn
must be associated with an ELF descriptor of class
.Dv ELFCLASS64 .
.Pp
Function
.Fn gelf_getshdr
copies the values in the section header associated with argument
.Ar scn
to the structure pointed to be argument
.Ar dst .
The
.Vt GElf_Shdr
data structure is described in
.Xr gelf 3 .
.Sh RETURN VALUES
Functions
.Fn elf32_getshdr
and
.Fn elf64_getshdr
return a valid pointer to the appropriate section header on success
or NULL if an error was encountered.
.Pp
Function
.Fn gelf_getshdr
returns argument
.Ar dst
if successful, or NULL if an error was encountered.
.Sh ERRORS
These functions may fail with the following errors:
.Bl -tag -width "[ELF_E_RESOURCE]"
.It Bq Er ELF_E_ARGUMENT
Arguments
.Ar scn
or
.Ar shdr
were NULL.
.It Bq Er ELF_E_ARGUMENT
Argument
.Ar scn
was not associated a descriptor for an ELF object.
.It Bq Er ELF_E_CLASS
The ELF class associated with the section descriptor
.Ar scn
did not match the class expected by the API.
.El
.Sh SEE ALSO
.Xr elf 3 ,
.Xr elf_getscn 3 ,
.Xr gelf 3 ,
.Xr gelf_update_shdr 3
